1. Field of the Invention
The present invention relates to a field of fluorescent powder manufacturing, and more particularly, to a fluorescent powder mixture which may increase the illumination efficiency of a field emission light source, a manufacturing method for the same, and a corresponding liquid crystal display device.
2. Description of the Prior Art
Liquid crystal displays have become mainstream displays because of having advantages of clear image quality, light and thin, portable, low power consumption, and long life. The backlight source used by a traditional liquid crystal display is mainly cold cathode fluorescent lamp (CCFL) and light emitting diode (LED). As a new type of surface light source, the field emission light source has advantages of high illumination efficiency, low power consumption, long lifetime, and easy to control. Therefore, the field emission light source has become a very promising backlight source of a liquid crystal display.
The operating principle of the field emission light source is to bombard the fluorescent powder by electron beams, so as to emit light. Generally speaking, carbon nanotube or ZnO nanoline are generally utilized as the cathode of the field emission light source, while the anode is fluorescent powder, and electron beams emitted from the cathode bombard the fluorescent powder to emit light. Currently, common fluorescent powder used for the field emission light source includes zinc sulfide and rare earth ion excited oxide or sulfur oxide. For sulfide fluorescent powder, the illumination brightness is higher. However, under the bombardment of the electron beams of a high beam density, decomposition will be easily happened to the sulfide, and makes the fluorescent powder have poor stability. For oxide fluorescent powder, it has higher stability, but the illumination efficiency is lower under the bombardment of the electron beams of low pressure. Meanwhile, the conductivity of the two materials is both poor. Thus, when the beam density of the electron beams is high, electron enrichment may easily occur on the surface of the fluorescent powder. Electron enrichment lowers the voltage between the cathode and the anode, then lowers the energy of the incident electron beam, and finally causes the illumination performance to decline.
Therefore, there is a need to provide a fluorescent powder mixture, a manufacturing method for the same, and a corresponding liquid crystal display device, so as to overcome the disadvantages in the prior art.